The PGA Tour's purse restrictions call for tiny bags, though, allowing a bag that is 6"x6" or smaller. Finding a purse 6 inches (roughly the length of a dollar bill) or smaller is tough. I scoured the internet for bags that work.

This is Only the Beginning
Expect restrictive bag and purse policies to become to the norm. Leagues and organizations claim that the policy is primarily for security, citing 2013's Boston Marathon bombing as the impetus for tighter restrictions.

One NFL source told me that these policies simply make the security screening process easier. Meaning fans can get into the game quicker because bags are easier to check and security screeners have fewer judgement calls to make.

The source indicated he wouldn't be surprised if the NBA and MLB followed suit.